Improvement in blind-stops



1-. H. GRANSTON.

Blind-Stops.

Patented Oct. 28,1873.

Ymebam UNITED STATES PA ENT ()FFIOE.

JOHN H. CRANSTON, OF NORWICH, CONNECTICUT.

- IMPROVEMENT lN BLIND'STOPS.

Specification forming part of Letters Patent No. 144,019, dated October 28, 1873; application filed October 2, 1873.

To all whom it may concern:

Be it known that I, J. H. ORANSTON, of Norwich, New London county, Connecticut, have invented certain Improvements relating to Blind-Slat Operators, of which thefollowing is a specification:

I attach a small rack-bar by means of a link to the rod to which the blind-slats are connected, and move the rack bar, and consequently operate the slats, by turning an endless screw, the threads of which screw take in the rack.

The rack, connecting-link, and screw may be made of malleable cast-iron, and sold as an article of builders hardware ready for attach ment to the blind.

The following is a description of what I consider the best means of carrying out the invention.

The accompanying drawings form a part of this specification.

Figure 1 is a front view; Fig. 2 is a vertical section and Fig. 3 is a section through a modification.

Similar letters of reference indicate corresponding parts in all the figures.

Referring to Figs. 1 and 2, Ais the main body of a blind, and B ordinary slats. C is an ordinary rod, to which the several slats are connected by staples b c in the usual manner. D is an attachment, of malleable cast iron or other suitable material, adapted to be screwed upon the lower rail of the blind, as represented. E is an endless screw, the thread of which is marked c. This screw E is mounted in fixed Gisa small bar of rectangular section, formed with teeth g, on one side making the rack-bar, by which term I will designate it. It is mounted vertically in the housing D, so that it is free to move endwise up and down. The thread 0 of the screw engages in the teeth 9 of the rackbar. A link, H, connects the rack-bar G g to the blind-rod C.

The friction of the screw holds the parts in any position in which they may be left. When it is desired to change the position of the blind slats the endless screw is turned. By its action the rack-bar G gis raised or lowered, and this, by means of the link H, correspondingly raises or lowers rod C and turns the slats B.

Many modifications in the details may be made by any good mechanic. 7

Fig. 3 shows one of these in which the rackbar Grv g is carried down through the center of the endless screw E c, and the thread e is made on the interior of the screw instead of on the exterior.

I prefer, however, the form and about the proportions indicated in Figs. 1 and 2.

I claim as my invention The frame or housing D, endless screw E 0, guided rack-bar G g, and link H, combined and arranged as and for the purposes herein specified.

In testimony whereof I have hereunto set my hand this 30th day of September, 187 3, in the presence of two subscribing witnesses.

J. H. CRANSTON.

Witnesses CHAS. D. NoYEs, WALTER FULLER. 

